Both players are in the England squad for next month's Euros.
"Theo and Alex can be the best players in the world because they have such an ability to play football," Sagna told The Sun.
"They are not scared to play and both started really young. Theo Walcott had a lot of pressure on him from a young age.
"He had a lot of pressure on him when he joined up with the national team for the first time at the age of 17.
"I know it is not easy to deal with but he did quite well. Of course he had to cope with a lot of criticism but he was younger then and he has a lot of maturity now.
"He was one of our main players this year along with Robin van Persie, scoring goals and creating assists and he can play a big, big part for the English national team this summer."